Hidenori Maezawa became a fan of music because his older brother was a huge fan of The Beatles. Although he enjoyed listening to music, he didn't decide to make his own music until he was 20. Maezawa wanted to play in a band, but he wasn't that great at playing instruments, so he began composing instead.

In 1986, while looking for a job in the magazine Being, Maezawa saw an opening at Konami for a gaming composer. His ability to both compose music and program computers was very useful and he was given the job. Maezawa then immediately began working on the audio of Castlevania, although he says he played only a minor role in the total audio.

Because of his technical skill, Maezawa was often in charge of porting the music from arcade versions of a game over to NES sound chip, a daunting task. During these ports, Maezawa sometimes had the ability to flex his creativity by compose new music to fit into new sections. Another benefit of being able to program is that Maezawa was involved in designing Konami's add-on chip for the NES called the VRC VI. Among other things, the chip allowed for improved audio capabilities, effectively doubling the NES's sound quality. The chip made its debut in 1989, but it was only used in a few Konami games only released in Japan, so most of the world didn't get to appreciate it.

Maezawa stayed in Kobe, Japan as a game composer for Konami until 1992 when he moved to Tokyo, Japan to be a music director for Konami's music label as the technology for putting chip tunes on CD was just being made. During that time, Maezawa saw many other fields in the music industry and decided to go out on his own. He started up his own company, Picnic. He uses Picnic to act as a middleman for the gaming industry and the music industry, which he claims is very different. Maezawa now makes music for various medias including game, pachinko machines, movies, and even traditional music. He has a album called Rain Book that he recorded with Japanese folk singer Yoko Yamamoto.